Data from the second black box recovered from the Germanwings plane wreckage has confirmed the co-pilot crashed the jet deliberately.
"A first reading shows that the pilot in the cockpit used the automatic pilot to descend the plane towards an altitude of 100ft (30m)," said the French BEA crash investigation office in a statement.
"Then, several times during the descent, the pilot changed the automatic pilot settings to increase the aircraft's speed."
The latest information appears to confirm the theory that co-pilot Andreas Lubitz (27) intentionally flew into the French Alps, killing all 150 people on board.
Authorities found the second black box, which contains technical flight data, on Thursday after a nine-day search in difficult mountain terrain.
Data from the first black box, which records conversations in the cockpit, suggested Mr Lubitz locked the captain out and then set the Airbus A320 on a collision course.
It smashed into the mountains at 430mph, instantly killing everyone on board. Half were German and more than 50 from Spain.
It emerged on Thursday that Lubitz had searched online for information about suicide and cockpit doors.
German prosecutors have said he was diagnosed as suicidal "several years ago" before he gained his pilot's licence.
Lufthansa, the parent company of Germanwings, has come under huge pressure after it was revealed Lubitz had told bosses he suffered from depression.
The German flag carrier said he had informed the airline about his illness in 2009 after interrupting his flight training.
No sign he intended to hurt himself or others
Doctors had recently found no sign he intended to hurt himself or others, although he had been signed off sick a number of times, including on the day of the crash.
Police found torn-up sick notes during a search of his apartment after the disaster.
The first black box suggested people were only aware of what was happening seconds before the plane, which was heading from Barcelona to Dusseldorf, crashed.
However, French and German media claim to have seen a video showing the final moments aboard the airliner, which they said was shot on a mobile phone found in the debris.
The video reportedly shows a chaotic scene with people screaming "my God" in several different languages.
On Thursday investigators said they had found mobile phones amongst the debris of the jet, although they had not yet produced any clues as to what happened.
John Litchfield is Paris correspondent with the London Independent.
He told Newstalk Lunchtime this black box data has removed all doubt over any accidental descent.
